US6414749B1 - Uneven-pattern reading apparatus - Google Patents

Uneven-pattern reading apparatus Download PDF

Info

Publication number
US6414749B1
US6414749B1 US09459925 US45992599A US6414749B1 US 6414749 B1 US6414749 B1 US 6414749B1 US 09459925 US09459925 US 09459925 US 45992599 A US45992599 A US 45992599A US 6414749 B1 US6414749 B1 US 6414749B1
Authority
US
Grant status
Grant
Patent type
Prior art keywords
light
surface
detecting
beam
incident
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
US09459925
Inventor
Tatsuki Okamoto
Yukio Sato
Junichi Nishimae
Hiroyuki Kawano
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Grant date

Links

Images

Classifications

    • GPHYSICS
    • G06COMPUTING; CALCULATING; COUNTING
    • G06KRECOGNITION OF DATA; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K9/00Methods or arrangements for reading or recognising printed or written characters or for recognising patterns, e.g. fingerprints
    • G06K9/00006Acquiring or recognising fingerprints or palmprints
    • G06K9/00013Image acquisition
    • G06K9/00046Image acquisition by using geometrical optics, e.g. using prisms

Abstract

An uneven-pattern reading apparatus includes a detecting prism having a detecting surface on which an uneven pattern is placed, an incident surface upon which an incident light beam for illuminating the uneven pattern is incident, and an emergent surface from which a light beam reflected from the uneven pattern on the detecting surface is emergent, angles between the respective detecting, incident, and emergent surfaces providing that the incident light beam is applied to the uneven pattern and the light reflected from the detecting surface is emergent from the emergent surface; an incident-light-beam converger for causing an incident light beam from a light source to be incident upon the incident surface after collimating or converging the incident light beam; an imaging device for detecting a reflected image emergent from the detecting prism; a converging optical system for collimating or converging the emergent light beam emergent from the emergent surface; and a processing device for identifying the uneven pattern on the basis of the image picked up by the imaging device, wherein an imaging surface of the imaging device is located closer to an emergent surface side than a focusing position of the converging optical system.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an uneven-pattern reading apparatus for reading an uneven surface pattern such as a fingerprint used for identifying an individual.

2. Description of the Related Art

FIG. 15 is a schematic diagram of a conventional uneven-pattern reading apparatus, which is disclosed in, for instance, Japanese Patent Unexamined Publication No. 13446/1980. Reference character L denotes an incident light beam from a light source. Numeral 4 denotes a detecting prism which is a base for placing a finger for detecting a fingerprint. Numeral 5 denotes a fingertip. Numeral 5 a denotes an uneven pattern such as a fingerprint. Numeral 7 denotes an imaging device for imaging the pattern of the fingerprint formed by a light beam which is emitted from the illuminating light and reflected from the finger. Numeral 8 denotes a processing device for processing the picked up image. Numeral 20 denotes an image-forming lens for forming an image of the pattern of the fingerprint on the imaging device. Numeral 21 denotes a television camera which is the imaging device. Numeral 41 denotes an incident surface of the detecting prism 4 upon which the light beam is made incident; 42 denotes a detecting surface of the detecting prism 4; and 43 denotes an emergent surface of the detecting prism 4 from which the reflected light beam is made emergent. Reference character L denotes the light beam.

Next, a description will be given of the operation. The fingertip 5 of a subject is brought into close contact with the detecting surface 42 of the detecting prism 4, and an incident light beam 1 incident upon the incident surface 41 of the detecting prism 4 is illuminated to the fingertip 5.

Here, if it is assumed that, at the detecting surface 42, the angle of incidence Θi of the light beam L is greater than or equal to a critical angle Θc with respect to an air layer, at the portion where the projecting surface of the fingerprint is in close contact, the light is transmitted through the interior of the finger, the amount of the reflected light beam from the detecting surface 42 is small. On the other hand, if there is an air layer formed by the detecting surface 42 and the projecting surface portions of the fingerprint at the finger tip 5, the incident light beam is totally reflected from the detecting surface 42.

Pattern information of the fingerprint, which is this reflected light beam, is outputted from the emergent surface 43 of the detecting prism 4. An image of this reflected light beam is formed on the imaging surface of the television camera 21 of the imaging device 7 to image the pattern of the fingerprint, and this pattern information is processed by the processing device 8, thereby making it possible to identify the fingerprint.

Since the conventional uneven-pattern reading apparatus is arranged such that the imaging surface of the imaging device 7 constitutes an imaging surface of the image-forming lens 20 with respect to the pattern of the subject, there has been a problem in that an optical path length of a predetermined length is required, making the apparatus large. In addition, there has been a problem, among others, in that if an attempt is made to make the apparatus compact by shortening the focal length, the pattern information becomes distorted, or a bright light source is required.

SUMMARY OF THE INVENTION

The present invention has been devised, and its object is to obtain a compact, lightweight uneven-pattern reading apparatus in which the optical path length from the detecting surface to the imaging surface is short.

An uneven-pattern reading apparatus in accordance with a first aspect of the present invention comprises: a detecting prism having a detecting surface on which an uneven pattern is placed, an incident surface upon which an incident light beam for illuminating the uneven pattern is incident, and an emergent surface from which a reflected light beam of the uneven pattern from the detecting surface is emergent, angles between the respective surfaces being provided such that the incident light beam is applied to the uneven pattern and the reflected light beam from the detecting surface is emergent from the emergent surface; incident-light-beam converging means for causing the incident light beam from a light source to be incident upon the incident surface after making the incident light beam from the light source parallel or convergent with respect to an optical axis of the incident light beam; an imaging device for picking up the reflected image emergent from the detecting prism; a converging optical system for converging the emergent light beam emergent from the emergent surface upon an imaging surface of the imaging device after making the emergent light beam emergent from the emergent surface parallel or convergent; and a processing device for identifying the uneven pattern on the basis of the image picked up by the imaging device, wherein an imaging surface of the imaging device is provided closer toward an emergent surface side than a focusing position of the converging optical system.

In an uneven-pattern reading apparatus in accordance with a second aspect of the present invention, vertical and horizontal magnifications of the incident-light-beam converging means or the emergent-light-beam converging means differ.

In an uneven-pattern reading apparatus in accordance with a third aspect of the present invention, the incident-light-beam converging means has diffusing means provided between the light source and the incident surface of the detecting prism for diffusing the light beam from the light source.

In an uneven-pattern reading apparatus in accordance with a fourth aspect of the present invention, the incident-light-beam converging means is arranged such that means for diffusing the light beam and means for making the light beam parallel or convergent are formed integrally.

In an uneven-pattern reading apparatus in accordance with a fifth aspect of the present invention, the detecting prism has means provided on the incident surface or the emergent surface for making the light beam parallel or convergent in a predetermined direction.

In an uneven-pattern reading apparatus in accordance with a sixth aspect of the present invention, the detecting prism has angles between surfaces for making the incident light beam and the emergent light beam parallel to the detecting surface.

In an uneven-pattern reading apparatus in accordance with a seventh aspect of the present invention, means for making the incident light beam upon the incident surface of the detecting prism has returning means for returning the light beam, the returning means being provided between the light source and the incident surface of the detecting prism or between the detecting surface and the imaging surface of the imaging device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a first embodiment;

FIGS. 2A and 2B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a second embodiment;

FIGS. 3A and 3B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a third embodiment;

FIGS. 4A and 4B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a fourth embodiment;

FIGS. 5A and 5B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a fifth embodiment;

FIGS. 6A and 6B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a sixth embodiment;

FIGS. 7A and 7B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a seventh embodiment;

FIGS. 8A and 8B are another schematic diagrams of the uneven-pattern reading apparatus in accordance with the seventh embodiment;

FIGS. 9A and 9B are schematic diagrams of an uneven-pattern reading apparatus in accordance with an eighth embodiment;

FIGS. 10A and 10B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a ninth embodiment;

FIG. 11 is another schematic diagram of the uneven-pattern reading apparatus in accordance with the ninth embodiment;

FIGS. 12A and 12B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a tenth embodiment;

FIGS. 13A and 13B are schematic diagrams of the uneven-pattern reading apparatus in accordance with the tenth embodiment;

FIG. 14 is still another schematic diagram of the uneven-pattern reading apparatus in accordance with the tenth embodiment; and

FIG. 15 is a schematic diagram of a conventional uneven-pattern reading apparatus.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

First Embodiment

FIGS. 1A and 1B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a first embodiment. FIG. 1A is a horizontal cross-sectional view, and FIG. 1B is an enlarged view of the portion of a detecting prism 4. Reference numeral 1 denotes a light source which emits an incident light beam L for illuminating an uneven pattern 5 a which is a fingerprint of a fingertip 5. Numeral 3 denotes a collimator lens which converts the incident light beam L from the light source 1 to a parallel or convergent light beam. The incident light beam L is made incident upon an incident surface 41 of the detecting prism 4 by means of the light source 1 and the collimator lens 3.

Reference numeral 4 denotes the detecting prism which detects the uneven pattern 5 a of the fingerprint of the fingertip 5 placed on a detecting surface 42, and is formed of, for instance, glass, resin, or the like. Numeral 41 denotes the incident surface of the detecting prism 4 upon which the light beam is made incident; 42 denotes the detecting surface of the detecting prism 4; and 43 denotes an emergent surface of the detecting prism 4 from which the light beam is made emergent.

The relationship between the direction of incidence of the incident light beam L and the incident surface of the detecting prism 4, which is shown in an enlarged view of the detecting prism 4 in FIG. 1B, is adjusted so that the incident light beam L is applied to the uneven pattern 5 a by adjusting the angle θA between the incident surface 41 and the detecting surface 42 of the detecting prism 4. In addition, adjustment is made so that the emergent light beam is made emergent in a predetermined direction by adjusting the angle θB between the detecting surface 42 and the emergent surface 43.

Further, the angle θ1 of incidence of the incident light beam L upon the detecting surface 42 of the detecting prism 4 is adjusted to such an angle that satisfies the condition of total reflection in a case where the outer side of the detecting prism 4 is the air layer and at which the light is transmitted in the case of a portion in close contact with the finger.

Reference numeral 6 denotes a reducing lens which is a converging optical system for converging the reflected image on the detecting surface 42 onto the imaging surface of an imaging device 7. Numeral 7 denotes the imaging device, and its imaging surface is provided in a nonfocal plane closer to an emergent surface of the reducing lens 6 than the focusing position of the reducing lens 6. That is, the imaging surface of the imaging device 7 is disposed at such a position that the distance from the detecting surface 42 of the detecting prism 4 to that position is shorter than the distance from the detecting surface 42 of the detecting prism 4 to the image forming plane of the reducing lens 6 in which the image of the uneven pattern 5 a is formed.

Hereafter, it is assumed that the image forming surface of the imaging device 7 shown in second to tenth embodiments is disposed in a similar relationship to the reducing lens 6.

Reference numeral 8 denotes a processing device which identifies the imaged uneven pattern 5 a by comparing the image picked up by the imaging device 7 with the uneven pattern 5 a such as the fingerprint which has been stored in advance. Since the other reference numerals denote members or portions that are similar to those of the conventional art, a description thereof will be omitted.

Next, a description will be given of the operation. Since the angle θ1 of incidence upon the detecting surface 42 is adjusted to such an angle that satisfies the condition of total reflection in a case where the outer side of the detecting surface 42 is the air layer and at which the light is transmitted in the case of a portion in close contact with the finger, it is possible to view a reflected image corresponding the unevenness of the fingerprint.

Further, if the pattern of a fingerprint imaged in the state in which the position of the imaging surface of the imaging device 7 is disposed at such a position that the distance from the detecting surface 42 to that position is shorter than the distance from the detecting surface 42 to the image forming plane is stored in advance, and if a newly imaged image pattern is compared by the processing device 8, it is possible to identify the imaged fingerprint.

In addition, since the position of the imaging surface of the imaging device 7 is disposed at such a position that the distance from the detecting surface 42 to that position is shorter than the distance from the detecting surface 42 to the image forming plane, it is possible to reduce the overall optical path length, so that it is possible to obtain a compact uneven-pattern reading apparatus.

Second Embodiment

FIGS. 2A and 2B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a second embodiment.

FIG. 2A is a plan view, and FIG. 2B is a cross-sectional view taken along line Ia—Ia of FIG. 2A. Reference numeral 2 denotes a light source which forms the light beam L with an elliptical cross section in which its horizontal angle of divergence θ// and its vertical angle of divergence θ⊥ differ. A semiconductor laser, for example, is used as the light source 2.

The detecting prism 4 is arranged such that the light beam 1 incident from the incident surface 41 is adjusted to an angle at which the light beam 1 is illuminated onto the detecting surface 42 in such a manner as to be enlarged in its vertical direction. Further, the light beam 1 is adjusted so as to be made emergent from the emergent surface 43 in such a manner as to be reduced in its vertical direction. Numeral 11 denotes a cylindrical lens for converging the reflected image from the detecting surface 42 onto the imaging surface of the imaging device 7, and is a lens for reducing only the reflected light in the horizontal direction.

In addition, with the uneven-pattern reading apparatus shown in FIGS. 2A and 2B, the angle θA between the detecting surface 42 of the detecting prism 4 and the incident surface 41 as well as the angle θB between the detecting surface 42 and the emergent surface 43 are set so that the incident light beam and the emergent light beam become parallel to the detecting surface of the detecting prism 4.

Next, a description will be given of the operation of the uneven-pattern reading apparatus in accordance with the second embodiment. The light, e.g. laser light, from a light source whose divergent angles in the horizontal direction and the vertical direction differ, is collimated to a light beam whose beam widths in the horizontal direction and the vertical direction differ by the collimator lens 3; however, if the light beam is made incident upon the detecting prism 4, the light beam L incident through the incident surface 41 is enlarged on the detecting surface 42 in the vertical direction, thereby making it possible to illuminate the overall uneven pattern.

Further, as shown in FIG. 2A since the light beam in the horizontal direction only is converged by the cylindrical lens 11, the reflected image in the horizontal direction which is wider than the size of the imaging surface of the imaging device 7 is reduced. As shown in FIG. 2B, the length of the reflected image in the vertical direction with a width shorter than that of the imaging surface remains as it is, thereby making it possible to converge the overall reflected image onto the imaging surface.

Accordingly, even if light sources whose vertical and horizontal divergent angles differ are used, it is possible to obtain a compact uneven-pattern reading apparatus.

Further, since the angle θA between the detecting surface 42 of the detecting prism 4 and the incident surface 41 as well as the angle θB between the detecting surface 42 and the emergent surface 43 are set so that the incident light beam and the emergent light beam become parallel, the apparatus can be made thin, thereby making it possible to obtain a compact uneven-pattern reading apparatus.

Third Embodiment

FIGS. 3A and 3B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a third embodiment, and illustrates the arrangement of a section of emergence from the detecting prism 4. FIG. 3A is a plan view, and FIG. 3B is a cross-sectional view taken along line Ib—Ib of FIG. 3A. Reference numeral 13 denotes a reducing prism, which is a prism for reducing only the horizontal length. Since the other reference numerals denote members or portions that are similar to those of the second embodiment, a description thereof will be omitted.

By using the reducing prism 13 instead of the cylindrical lens 11 in FIGS. 2A and 2B, it is possible to obtain advantages similar to those of the uneven-pattern reading apparatus in accordance with the second embodiment.

Fourth Embodiment

FIGS. 4A and 4B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a fourth embodiment. FIG. 4A is a plan view, and FIG. 4B is a cross-sectional view taken along line Ic—Ic of FIG. 4A. Reference numeral 7 a denotes an imaging device having an imaging surface with the same area as that of the emergent surface in terms of both the horizontal and vertical directions.

Since the imaging device 7 a having a sufficient imaging area, the lens for reducing the reflected image is made unnecessary, so that it is possible to obtain a further compact uneven-pattern reading apparatus.

Fifth Embodiment

FIGS. 5A and 5B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a fifth embodiment. FIG. 5A is a plan view, and FIG. 5B is a cross-sectional view taken along line Id—Id of FIG. 5A. Reference numeral 9 denotes a concave lens for enlarging the angle of divergence of the light beam L from the light source 1. Since the other reference numerals denote members or portions that are similar to those of the first to fourth embodiments, a description thereof will be omitted.

Next, a description will be given of the operation of the uneven-pattern reading apparatus in accordance with the fifth embodiment. Since the angle of divergence of the light beam L from the light source 1 is enlarged by the concave lens 9, it is possible to allow the light beam with an area capable of illuminating the overall detecting surface to be incident upon the collimator lens 3 at a distance close to the light source 1.

It should be noted that if the light source 1 is adapted to emit the light uniformly in the vertical and horizontal directions, the collimator lens 3 in FIGS. 5A and 5B can be omitted, and if the light is diverged by the concave lens 9 located in close proximity to the incident surface 41 from the light source 1, and is then made directly incident upon the incident surface 41, the distance between the concave lens 9 and the incident surface 41 can be made short.

Accordingly, the distance from the light source 1 to the collimator lens 3 can be made short, so that it is possible to obtain a compact uneven-pattern reading apparatus with a short overall length.

Sixth Embodiment

FIGS. 6A and 6B is a schematic diagram of an uneven-pattern reading apparatus in accordance with a sixth embodiment. FIG. 6A is a plan view, and FIG. 6B is a cross-sectional view taken along line Ie—Ie of FIG. 6A. Reference numeral 3 b denotes a collimator lens which is obtained by integrally forming the concave lens 9 and the collimator lens 3 in FIGS. 5A and 5B. Since the other reference numerals denote members or portions that are similar to those of the first to fifth embodiments, a description thereof will be omitted.

Thus, with the uneven-pattern reading apparatus in accordance with the sixth embodiment, since the concave lens 9 and the collimator lens 3 in FIGS. 5A and 5B are formed integrally, the number of component parts can be reduced, thereby making it possible to obtain a compact uneven-pattern reading apparatus.

Seventh Embodiment

FIGS. 7A and 7B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a seventh embodiment. FIG. 7A is a plan view, and FIG. 7B is a cross-sectional view taken along line If—If of FIG. 7A. Reference numeral 10 denotes a collimating fresnel lens which is formed integrally on the incident surface 41 of the detecting prism 4 so as to convert the incident light beam L into a parallel beam or convergent beam inside the detecting prism 4. Since the other reference numerals denote members or portions that are similar to those of the first to third embodiments, a description thereof will be omitted.

Next, a description will be given of the uneven-pattern reading apparatus in accordance with the seventh embodiment. Since the incident light beam L can be applied to the overall detecting surface 42 as the parallel beam or convergent beam inside the detecting prism 4 by the collimating fresnel lens 10, the collimator lens 3 can be omitted, so that the number of component parts can be reduced, thereby making it possible to obtain a compact uneven-pattern reading apparatus.

FIGS. 8A and 8B are another schematic diagrams of the uneven-pattern reading apparatus in accordance with the seventh embodiment. FIG. 8A is a plan view, and FIG. 8B is a cross-sectional view taken along line Ig—Ig of FIG. 8A. Since the angle between the incident surface 41 and the detecting surface 42 of the detecting prism 4 is made orthogonal and the shape is simplified, so that it is possible to obtain a compact uneven-pattern reading apparatus in its assembled form.

Eighth Embodiment

FIGS. 9A and 9B are schematic diagrams of an uneven-pattern reading apparatus in accordance with an eighth embodiment. FIG. 9A is a plan view, and FIG. 9B is a cross-sectional view taken along line Ih—Ih of FIG. 9A. Reference numeral 4 b denotes a detecting prism in which fresnel lenses are provided on the incident surface 41 and the emergent surface 43 for making the light beam parallel or convergent in a predetermined direction. Reference numeral 10 denotes the collimating fresnel lens provided on the incident surface 41 so as to allow the incident light beam to be applied to the overall detecting surface. Numeral 14 denotes a reducing fresnel lens provided on the emergent surface 43 so as to converge the emergent light onto the imaging surface of the imaging device 7. Since the other reference numerals denote members or portions that are similar to those of the first to seventh embodiments, a description thereof will be omitted.

Next, a description will be given of the uneven-pattern reading apparatus in accordance with the eighth embodiment. Since the collimating fresnel lens 10 for allowing the incident light beam to be applied to the overall detecting surface is provided on the incident surface 41 of the detecting prism 4 b, and the reducing fresnel lens 14 for converging the emergent light onto the imaging surface of the imaging device 7 is provided on the emergent surface 43, the collimator lens 3 or the reducing lens 6 can be omitted. Hence, it is possible to obtain a compact uneven-pattern reading apparatus.

Ninth Embodiment

FIG. 10A is a schematic diagram of an uneven-pattern reading apparatus in accordance with a ninth embodiment. FIG. 10B is another schematic diagram of the uneven-pattern reading apparatus in accordance with the ninth embodiment. In the uneven-pattern reading apparatus in accordance with the ninth embodiment, a polygonal deformed detecting prism is adopted. In FIG. 10A, reference numeral 4 c denotes a trapezoidal detecting prism. Disposed on the respective slanting surfaces of the trapezoid of the detecting prism 4 c are a collimating mirror 17 for reflecting in a predetermined direction the incident light beam L incident from below upon the detecting prism 4 c and for applying the incident light beam L to the overall detecting surface, as well as a reducing-mirror 18 for reflecting the reflected image from the detecting surface and for converging the reflected image onto the imaging surface of the imaging device 7.

In addition, in FIG. 10B, reference numeral 4 d denotes a rectangular detecting prism which is provided with the collimating mirror 17 for reflecting in a predetermined direction the incident light beam L incident from below upon the detecting prism 4 c and for applying the incident light beam L to the overall detecting surface, as well as the reducing mirror 18 for reflecting the reflected image from the detecting surface and for converging the reflected image onto the imaging surface of the imaging device 7. In addition, the rectangular detecting prism 4 d is provided with a cavity portion in a bottom portion of the rectangular detecting prism 4 d, and the light source 1 and the imaging device 7 are also provided therein.

FIG. 11 is still another schematic diagram of the uneven-pattern reading apparatus in accordance with the ninth embodiment. Reference numeral 4 e denotes a detecting prism which is arranged as follows. Instead of providing the collimating mirror 17 and the reducing mirror 18 on both side surfaces of the detecting prism 4 c in FIG. 10A, a collimating fresnel lens 10 a is provided on an incident surface 41 a, and a reducing fresnel lens 14 a is provided on an emergent surface 43 a. Since the other reference numerals denote members or portions that are similar to those of FIGS. 10A and 10B, splotch a description thereof will be omitted.

Next, a description will be given of the operation of the ninth embodiment. In the uneven-pattern reading apparatus in FIG. 10A or 10B, the collimating mirror 17 and the reducing mirror 18 are provided on both left- and right-hand sides of the polygonal deformed detecting prism 4 c or 4 d so as to reflect the light beam L inside the detecting prism 4 c or 4 d, thereby illuminating a predetermined detecting surface 42 a or 42 b and the imaging device 7. Accordingly, it is possible to shorten the overall length of the uneven-pattern reading apparatus, so that it is possible to obtain a compact uneven-pattern reading apparatus.

Tenth Embodiment

FIGS. 12A and 12B are schematic diagrams of an uneven-pattern reading apparatus in accordance with a 10th embodiment. FIG. 12A is a plan view, and FIG. 12B is a cross-sectional view taken along line Ii—Ii of FIG. 12A. Reference numeral 15 denotes a collimator with a prism, which causes the incident light beam from the light source to be incident upon the incident surface 41 of the detecting prism 4 after orthogonally bending the optical path of the incident light beam from the light source, and which is arranged such that a collimating fresnel lens is provided on the emergent surface of the collimator 15 with a prism. Numeral 16 denotes a reducing lens with a prism, which causes the emergent light beam from the emergent surface 43 of the detecting prism 4 upon the imaging surface of the imaging device 7 after orthogonally bending the optical path of the light beam L emergent from the emergent surface 43 of the detecting prism 4.

FIGS. 13A and 13B are another schematic diagrams of the uneven-pattern reading apparatus in accordance with the 10th embodiment. FIG. 13A is a plan view, and FIG. 13B is a cross-sectional view taken along line Ij—Ij of FIG. 13A. Reference numeral 15 a denotes a collimator with a prism, which causes the incident light beam from the light source to be incident upon the incident surface 41 of the detecting prism 4 after bending in the opposite direction the optical path of the incident light beam from the light source, and which is arranged such that a collimating fresnel lens is provided on the emergent surface of the collimator 15 with a prism. Since the other reference numerals denote members or portions that are similar to those of FIGS. 12A and 12B, a description thereof will be omitted.

FIG. 14 is still another schematic diagram of the uneven-pattern reading apparatus in accordance with the 10th embodiment. Instead of providing the reflecting fresnel lens 10 a on the incident surface of the detecting prism 4 c in FIG. 11 shown as the ninth embodiment, the collimator 15 a with a prism is provided.

Next, a description will be given of the operation of the uneven-pattern reading apparatus in accordance with the 10th embodiment. Since returning means for returning the light beam are provided between the light source and the incident surface of the detecting prism and between the detecting surface and the imaging surface of the imaging device, it is possible to shorten the overall length of the uneven-pattern reading apparatus. Accordingly, it is possible to obtain a compact uneven-pattern reading apparatus.

As described above, in accordance with the first aspect of the present invention the uneven-pattern reading apparatus comprises: a detecting prism having a detecting surface on which an uneven pattern is placed, an incident surface upon which an incident light beam for illuminating the uneven pattern is incident, and an emergent surface from which a reflected light beam of the uneven pattern from the detecting surface is emergent, angles between the respective surfaces being provided such that the incident light beam is applied to the uneven pattern and the reflected light beam from the detecting surface is emergent from the emergent surface; incident-light-beam converging means for causing the incident light beam from the light source to be incident upon the incident surface after making the incident light beam from the light source parallel or convergent with respect to an optical axis of the incident light beam; an imaging device for picking up the reflected image emergent from the detecting prism; a converging optical system for converging the emergent light beam emergent from the emergent surface upon an imaging surface of the imaging device after making the emergent light beam emergent from the emergent surface parallel or convergent; and a processing device for identifying the uneven pattern on the basis of the image picked up by the imaging device, wherein an imaging surface of the imaging device is provided closer toward an emergent surface side than a focusing position of the converging optical system. Therefore, it is possible to reduce the overall optical path length, so that a compact uneven-pattern reading apparatus can be obtained.

In accordance with the second aspect of the present invention, vertical and horizontal magnifications of the incident-light-beam converging means or the emergent-light-beam converging means differ. Therefore, even if light sources whose vertical and horizontal divergent angles differ are used, it is possible to obtain a compact uneven-pattern reading apparatus.

In accordance with the third aspect of the present invention, the incident-light-beam converging mean s has diffusing means provided between the light source and the incident surface of the detecting prism for diffusing the light beam from the light source. Therefore, the distance from the light source 1 to the collimator lens 3 can be shortened, so that it is possible to obtain a compact uneven-pattern reading apparatus whose overall length is short.

In accordance with the fourth aspect of the present invention, the incident-light-beam converging means is arranged such that means for diffusing the light beam and means for making the light beam parallel or convergent are formed integrally. Therefore, it is possible to reduce the number of component parts, and a compact uneven-pattern reading apparatus can be obtained.

In accordance with the fifth aspect of the present invention, the detecting prism has collimating means provided on the incident surface or the emergent surface for making the light beam parallel or convergent in a predetermined direction. Therefore, it is possible to reduce the number of component parts, and a compact uneven-pattern reading apparatus can be obtained.

In accordance with the sixth aspect of the present invention, the detecting prism has angles between surfaces for making the incident light beam and the emergent light beam parallel to the detecting surface. Accordingly, it is possible to obtain a thin and compact uneven-pattern reading apparatus.

In accordance with the seventh aspect of the present invention, means for making the incident light beam upon the incident surface of the detecting prism has returning means for returning the light beam, the returning means being provided between the light source and the incident surface of the detecting prism or between the detecting surface and the imaging surface of the imaging device. Therefore, it is possible to obtain a compact uneven-pattern reading apparatus whose overall length is short.

Claims (7)

What is claimed is:
1. An uneven-pattern reading apparatus comprising:
a detecting prism having a detecting surface on which an uneven pattern is placed, an incident surface upon which an incident light beam for illuminating the uneven pattern is incident, and an-emergent surface from which a light beam reflected from the uneven pattern on the detecting surface is emergent, angles between the respective incident, detecting, and emergent surfaces providing that the incident light beam is applied to the uneven pattern and the light reflected from the detecting surface is emergent from the emergent surface;
incident-light-beam converging means for collimating or converging the incident light beam from a light source before incidence on the incident surface;
an imaging device for detecting a reflected image emergent from said detecting prism;
a converging optical system for converging the emergent light beam emergent from the emergent surface upon an imaging surface of said imaging device after collimating or converging the emergent light; and
a processing device for identifying the uneven pattern on the basis of the image detected by said imaging device, wherein the imaging surface of said imaging device is located closer to an emergent surface side than a focusing position of said converging optical system.
2. The uneven-pattern reading apparatus according to claim 1, wherein vertical and horizontal magnifications of one of said incident-light-beam converging means and said converging optical system differ.
3. The uneven-pattern reading apparatus according to claim 1, wherein said incident-light-beam converging means has diffusing means located between said light source and the incident surface of said detecting prism for diffusing the light beam from said light source.
4. The uneven-pattern reading apparatus according to claim 2, wherein said incident-light-beam converging means includes integral means for diffusing the light beam and means for collimating or converging the light beam.
5. The uneven-pattern reading apparatus according to claim 1, wherein said detecting prism has collimating means located on one of the incident surface and the emergent surface for collimating the light beam in a predetermined direction.
6. The uneven-pattern reading apparatus according to claim 1, wherein the angles between the detecting, incident, and emergent surfaces make the incident light beam and the emergent light-beam parallel to the detecting surface.
7. The uneven-pattern reading apparatus according to claim 1, including returning means for returning the light beam, said returning means being located between one of (i) said light source and the incident surface of said detecting prism and (ii) the detecting surface and the imaging surface of said imaging device.
US09459925 1998-12-24 1999-12-14 Uneven-pattern reading apparatus Expired - Fee Related US6414749B1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP36784498A JP2000194829A (en) 1998-12-24 1998-12-24 Irregular pattern reader
JP10-367844 1998-12-24

Publications (1)

Publication Number Publication Date
US6414749B1 true US6414749B1 (en) 2002-07-02

Family

ID=18490344

Family Applications (1)

Application Number Title Priority Date Filing Date
US09459925 Expired - Fee Related US6414749B1 (en) 1998-12-24 1999-12-14 Uneven-pattern reading apparatus

Country Status (2)

Country Link
US (1) US6414749B1 (en)
JP (1) JP2000194829A (en)

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20030104186A1 (en) * 1999-11-10 2003-06-05 Ibiden Co., Ltd. Ceramic substrate
US20030111534A1 (en) * 2001-12-14 2003-06-19 Juergen Hillmann Method and arrangement for low-distortion recording of intensity patterns occurring on a contact surface through frustrated total reflection
US20030133103A1 (en) * 2002-01-17 2003-07-17 Arnold Joseph F. Systems and methods for illuminating a platen in a print scanner
US20030206287A1 (en) * 2002-01-17 2003-11-06 Cross Match Technologies, Inc. Light wedge for illuminating a platen in a print scanner
US6912300B1 (en) * 1999-08-20 2005-06-28 Mitsubishi Denki Kabushiki Kaisha Irregular pattern reader
US20060291704A1 (en) * 2005-06-10 2006-12-28 Mcclurg George W Apparatus and method for obtaining images using a prism
FR2952801A1 (en) * 2009-11-20 2011-05-27 Sagem Securite Cutaneous fingerprint sensor e.g. digital fingerprint sensor, for providing relief alternations and furrows in cutaneous surface of user, has sheet comprising pattern that is applied in such manner that ray is compared to optical axis
US8073209B2 (en) 2002-01-17 2011-12-06 Cross Match Technologies, Inc Biometric imaging system and method
CN102810029A (en) * 2011-06-02 2012-12-05 全视科技有限公司 Optical touchpad for touch and gesture recognition
CN103929566A (en) * 2013-01-15 2014-07-16 富士通株式会社 Biometric Information Image-capturing Device And Biometric Authentication Apparatus
US20140376784A1 (en) * 2012-03-28 2014-12-25 Fujitsu Limited Biometric authentication device, biometric authentication method, and computer readable, non-transitory medium

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009285278A (en) * 2008-05-30 2009-12-10 Hitachi Maxell Ltd Biological information acquisition apparatus, biometric authentication apparatus, and light guide
JP2016507800A (en) * 2013-11-08 2016-03-10 株式会社ユニオンコミュニティUnioncommunity Co.,Ltd Fingerprint input device camera using a mobile terminal that is mounted and exterior optics for the fingerprint input
JP5950121B2 (en) * 2013-12-27 2016-07-13 日本電気株式会社 Authentication device
JP6032454B2 (en) * 2016-04-06 2016-11-30 日本電気株式会社 Imaging device

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5596454A (en) 1994-10-28 1997-01-21 The National Registry, Inc. Uneven surface image transfer apparatus
US5621516A (en) 1994-02-04 1997-04-15 Fujitsu Limited Optical device for forming an image of an uneven surface
US5625448A (en) 1995-03-16 1997-04-29 Printrak International, Inc. Fingerprint imaging
US6127674A (en) * 1997-09-01 2000-10-03 Fujitsu Limited Uneven-surface data detection apparatus
US6240200B1 (en) * 1997-08-29 2001-05-29 Barry M. Wendt Optical fingerprint imager with improved optics

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5621516A (en) 1994-02-04 1997-04-15 Fujitsu Limited Optical device for forming an image of an uneven surface
US5596454A (en) 1994-10-28 1997-01-21 The National Registry, Inc. Uneven surface image transfer apparatus
US5625448A (en) 1995-03-16 1997-04-29 Printrak International, Inc. Fingerprint imaging
US6240200B1 (en) * 1997-08-29 2001-05-29 Barry M. Wendt Optical fingerprint imager with improved optics
US6127674A (en) * 1997-09-01 2000-10-03 Fujitsu Limited Uneven-surface data detection apparatus

Cited By (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6912300B1 (en) * 1999-08-20 2005-06-28 Mitsubishi Denki Kabushiki Kaisha Irregular pattern reader
US20030104186A1 (en) * 1999-11-10 2003-06-05 Ibiden Co., Ltd. Ceramic substrate
US20030111534A1 (en) * 2001-12-14 2003-06-19 Juergen Hillmann Method and arrangement for low-distortion recording of intensity patterns occurring on a contact surface through frustrated total reflection
US7130456B2 (en) * 2001-12-14 2006-10-31 Smiths Heimann Biometrics Gnbh Method and arrangement for low-distortion recording of intensity patterns occurring on a contact surface through frustrated total reflection
US20030206287A1 (en) * 2002-01-17 2003-11-06 Cross Match Technologies, Inc. Light wedge for illuminating a platen in a print scanner
US8073209B2 (en) 2002-01-17 2011-12-06 Cross Match Technologies, Inc Biometric imaging system and method
EP1474773A1 (en) * 2002-01-17 2004-11-10 Cross Match Technologies, Inc. Systems and methods for illuminating a platen in a print scanner
US6867850B2 (en) * 2002-01-17 2005-03-15 Cross Match Technologies, Inc. Light wedge for illuminating a platen in a print scanner
US20030133103A1 (en) * 2002-01-17 2003-07-17 Arnold Joseph F. Systems and methods for illuminating a platen in a print scanner
US6954260B2 (en) * 2002-01-17 2005-10-11 Cross Match Technologies, Inc. Systems and methods for illuminating a platen in a print scanner
US20060170906A1 (en) * 2002-01-17 2006-08-03 Cross Match Technologies, Inc. Systems and methods for illuminating a platen in a print scanner
EP1474773A4 (en) * 2002-01-17 2006-08-30 Cross Match Technologies Inc Systems and methods for illuminating a platen in a print scanner
US7271881B2 (en) * 2002-01-17 2007-09-18 Cross Match Technologies, Inc. Systems and methods for illuminating a platen in a print scanner
WO2004092926A2 (en) * 2003-04-09 2004-10-28 Cross Match Technologies, Inc. Light wedge for illuminating a platen in a print scanner
WO2004092926A3 (en) * 2003-04-09 2005-02-24 Cross Match Technologies Inc Light wedge for illuminating a platen in a print scanner
US7747046B2 (en) 2005-06-10 2010-06-29 Cross Match Technologies, Inc. Apparatus and method for obtaining images using a prism
US20100322537A1 (en) * 2005-06-10 2010-12-23 Mcclurg George W Apparatus and Method for Obtaining Images Using a Prism
US7953259B2 (en) 2005-06-10 2011-05-31 Cross Match Technologies, Inc. Apparatus and method for obtaining images using a prism
US20060291704A1 (en) * 2005-06-10 2006-12-28 Mcclurg George W Apparatus and method for obtaining images using a prism
FR2952801A1 (en) * 2009-11-20 2011-05-27 Sagem Securite Cutaneous fingerprint sensor e.g. digital fingerprint sensor, for providing relief alternations and furrows in cutaneous surface of user, has sheet comprising pattern that is applied in such manner that ray is compared to optical axis
US9213438B2 (en) * 2011-06-02 2015-12-15 Omnivision Technologies, Inc. Optical touchpad for touch and gesture recognition
CN102810029A (en) * 2011-06-02 2012-12-05 全视科技有限公司 Optical touchpad for touch and gesture recognition
CN102810029B (en) * 2011-06-02 2016-04-13 全视科技有限公司 Optical touch gesture recognition and a touch pad
US20120306815A1 (en) * 2011-06-02 2012-12-06 Omnivision Technologies, Inc. Optical touchpad for touch and gesture recognition
US20140376784A1 (en) * 2012-03-28 2014-12-25 Fujitsu Limited Biometric authentication device, biometric authentication method, and computer readable, non-transitory medium
US9336426B2 (en) * 2012-03-28 2016-05-10 Fujitsu Limited Biometric authentication device, biometric authentication method, and computer readable, non-transitory medium
US20140198957A1 (en) * 2013-01-15 2014-07-17 Fujitsu Limited Biometric information image-capturing device, biometric authentication apparatus and manufacturing method of biometric information image-capturing device
CN103929566A (en) * 2013-01-15 2014-07-16 富士通株式会社 Biometric Information Image-capturing Device And Biometric Authentication Apparatus
US9336427B2 (en) * 2013-01-15 2016-05-10 Fujitsu Limited Biometric information image-capturing device, biometric authentication apparatus and manufacturing method of biometric information image-capturing device

Also Published As

Publication number Publication date Type
JP2000194829A (en) 2000-07-14 application

Similar Documents

Publication Publication Date Title
US5796858A (en) Fingerprint sensing system using a sheet prism
US5596454A (en) Uneven surface image transfer apparatus
US5146102A (en) Fingerprint image input apparatus including a cylindrical lens
US5537247A (en) Single aperture confocal imaging system
US6078419A (en) Optical scanning apparatus with design flexibility
US20020018310A1 (en) Optical path folding apparatus
US20070070302A1 (en) Speckle reduction in laser illuminated projection displays having a one-dimensional spatial light modulator
US6711319B2 (en) Optical switch with converging optical element
US20030117602A1 (en) Projection aligner
US6637894B2 (en) High contrast projection
US6039254A (en) Method for imaging bar codes
EP0308162A2 (en) Optical system for fingerprint imaging
US5109427A (en) Fingerprint recognition device using a hologram
US6956608B1 (en) Fingerprint imaging device including an optical plate having microreflectors
US5894345A (en) Optical method of detecting defect and apparatus used therein
US4783167A (en) Finger imaging apparatus using curved platen
US6826000B2 (en) Optical fingerprint acquisition apparatus
US4756585A (en) Optical beam scanning system
US20120038986A1 (en) Pattern projector
US5187748A (en) Optical apparatus for fingerprint identification system
US6400905B1 (en) Lighting angle variable lighting device
US6565248B2 (en) Light guide, line illumination apparatus, and image acquisition system
US5448659A (en) Waveguide-type image transmission device and fingerprint identification device
US6435411B1 (en) Optoelectronic device for acquisition of images, in particular of bar codes
US5907438A (en) Imaging device

Legal Events

Date Code Title Description
AS Assignment

Owner name: MITSUBISHI DENKI KABUSHIKI KAISHA, JAPAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:OKAMOTO, TATSUKI;SATO, YUKIO;NISHIMAE, JUNICHI;AND OTHERS;REEL/FRAME:010463/0750

Effective date: 19991203

FPAY Fee payment

Year of fee payment: 4

FPAY Fee payment

Year of fee payment: 8

REMI Maintenance fee reminder mailed
LAPS Lapse for failure to pay maintenance fees
FP Expired due to failure to pay maintenance fee

Effective date: 20140702